The present invention relates to vehicle warning systems, and more particularly to a system and method for detection of objects behind the vehicle and classification of the objects.
Motor vehicles, especially sport utility vehicles (SUV), pick-up trucks and off-road vehicles typically have a “blind” zone behind the vehicles which is a contributing cause for accidents when the vehicles are driven in reverse. The “blind” zone cannot be viewed directly by the driver nor with the use of the vehicle mirrors. Motor vehicle accidents involving vehicles being driven in reverse cause vehicle damage there is a collision with typically low obstructions, e.g. walls and poles, and serious accidents involving children.
In an effort to reduce the frequency and severity of vehicular accidents involving vehicles being driven in reverse, vehicle manufacturers have introduced rear-view cameras mounted on the vehicle which image the “blind” zone behind the vehicle.
U.S. Pat. No. 7,113,867 disclosed by the present inventor system is designed to detect objects in front of the vehicle. A camera is mounted inside a vehicle behind the windshield, and views the environment through the windshield in front of vehicle. A processor analyzes the images acquired by the camera. The system is operative to detect lane markings, pedestrians, other vehicles, obstacles, road signs, and/or other objects up to relatively long distances, typically 50-100 meters from the front of the vehicle.
Recognition of obstacles located behind a vehicle present a different set of image processing issues than addressed by a forward-looking camera system. Obstacles located behind a vehicle may be stationary or slowly moving, and at close range, at one to two meters. An additional factor to be considered is that vehicles move in reverse under 10 km/hour.
Rear looking camera systems which provide the driver additional visibility using an attached monitor, for example parking assist systems, and blind spot detection systems are known in the industry, but unlike the forward looking camera systems, these reverse looking camera systems provide the driver images on the monitor without providing any analysis of the images or warning of the existence of an obstacle behind the vehicle or of an expected collision with an obstacle.
There is thus a need for, and it would be highly advantageous to have a rear viewing camera system mounted in a vehicle which provides analysis for particularly common classes of obstacles typically found behind a vehicle and warnings to the driver based on the analysis when such obstacles are found.
European Patent EP 1876829 discloses a vehicle vicinity monitoring system which captures images of the vicinity of the vehicle using an image-capturing device, and uses a notification device to provide vehicle occupants with information concerning obstacles in the vicinity of the vehicle. A primary lighting device and/or a secondary lighting device are provided to the vehicle. The primary lighting device directs light upon shadows cast within the imaging field of the image-capturing device as a result of the illumination device being illuminated. The secondary lighting device is a lighting device for projecting light in a prescribed pattern within the imaging field of the image-capturing device in order to confirm the existence of an obstacle.